The LinkedIn Discussion Group, “SleepDisordersDentistry” has just completed an open discussion on establishing an Oral Appliance Starting Position. Here is a consensus for all to ponder.

What was asked,

“Our next discussion will be “Establishing Oral Appliance Starting Position”. We’ve already heard a great deal from both the Phonetic and George Gauge Groups, but there are many other approaches and ideas such as the Apnea Guard, Airway Metrics, Andra Gauge, MATRx etc. I have even heard of clinicians using a “Golf Tee” to establish their initial bite registration!

There is very little in the literature about “Establishing Oral Appliance Starting Position”; so it would be very interesting to hear about various techniques and methods, and what works for clinicians around the world…”

What was said,

Our discussion on “Establishing an Oral Appliance Starting Position” confirms much agreement amongst our peers that there is no universal “Evidenced Based”, or “Anecdotally Based” starting point that will assure the best outcome; most clinician’s relying on the only Evidenced Based Data, “Jaw Advancement” while keeping “Vertical to a Minimum”. However a scattering of very unique ideas were also discussed, including some new Evidence Based technologies that provide valuable information regarding both efficacy and starting position. Our longest discussion to date included some very heated posts, that were at times entertaining, at other times insightful and occasionally could be considered an outright “cyber” fistfight. I encourage you to take the time to review the following synopsis on the many ideas expressed by clinicians that actually do this work on a daily basis in their clinics.

Mandibular advancement:

The majority of discussion revolved around some degree of mandibular advancement (the only Evidence Based approach). As a starting point, most clinicians advance the mandible approximately 60-70 % of the protrusive range, and then make various “Consideration Adjustments” from that position which results in the final “Starting Position”. The various “Consideration Adjustments” mentioned were:

Patient comfort (trumps all)

Results of muscle, ligament and joint palpation exams

Appliance design, (ensuring that the selected position still enabled the patient to reach their maximum protrusive position when considering the chosen appliances unique adjustment range, keeping in mind that for some patients, protrusive range increases with appliance wear)

Apnea Severity (less advancement for less severe apnea)

Urgency to obtain optimum outcome

Once a position is established, Barry Glassman discussed having the patient clench their teeth in the George Gauge, and then go to each lateral position and have the patient clench again, looking for tenderness or tightness in the contralateral joint. If this tests positive, a less (or more) protruded position would be established, followed by retesting.
It was pointed out that this 60-70% of protrusive position has little science behind it, so it makes more sense to work back from maximum protrusive based on the unique adjustment range of the chosen appliance as a start position, and then make the “Consideration Adjustments”. I found the drama over this part of the discussion quite entertaining. When one considers what 60-70% of a “typical” range of motion is, and how it compares to the position you end up with when you work back from maximum protrusive by the amount of adjustability of a “typical” appliance (approximately 5mm), the two positions of course vary, but are somewhat similar, yet this resulted in so much debate! What made this part of the discussion even more entertaining was that pretty well everyone agreed that this final position would be tweaked further, based on the “Consideration Adjustments”. Quite frankly, especially once you consider the “Consideration Adjustments ”, I don’t see any material difference between these two approaches for the majority of people. Just do the math and you’ll see what I mean. Just sayn’;). Kent Smith said it best and with the most honesty, “Hey, it’s all a guess anyway!”

So, in the end, it seems clinicians in this group advance the mandible using a set formula (which often results in a similar position for all) and then adjust that position forward or back based on certain “Consideration Adjustments” to establish the Starting Position. It was also pointed out that some patients experience maximum benefit by simply preventing the jaw from falling back, with no forward protrusion at all. However, the bite position should be advanced a minimum of 1 to 2 mm from “centric” to prevent translation/rotation out of appliance as advancement decreases the opening potential (particularly useful with the dorsal design).

For patients overly concerned about possible bite changes, it was suggested that less advancement be considered. A study conducted by Doff et al. March 2013 “Long Term OA Therapy in OSAS”, documented the following, “Linear regression analysis revealed that the decrease in overbite was associated with the mean mandibular protrusion during follow-up [regression coefficient (beta) = -0.02, 95 % confidence interval (-0.04 to -0.00)]”; suggesting that this type of tooth movement could be minimized with less advancement.

Although there are various tools available to facilitate taking a mandibular advancement bite registration (George Gauge, Pro Gauge, Andra Gauge etc), it seems that the George Gauge with the 2 mm bite fork was the most common tool used. The 5 mm bite fork was recommended when an increased vertical was sought. Modification to the George Gauge was also mentioned; placing wax in the “V” groove to increase the vertical and drilling out the “V Groove” so it better accommodates misaligned teeth. Whichever tool is used, it was recommended that the patient not clench into it when taking the bite registration.

Right off the bat, I feel it is worthwhile to mention that the variety of appliances currently available range widely in Vertical, yet there is no evidence in the literature that one appliance results in a superior outcome to another. Moreover, there is very little research on vertical and it mostly supports keeping it to a minimum (Petsis, 2002). However, anecdotally, it seems that a subset of patients benefit from varying vertical. In approximately 2005, even Alan Lowe came forward on this issue and after years of stating that the vertical should be kept to a minimum, he admitted that in a subset of patients, an increase in vertical results in a better outcome. However, personally I have been less concerned with altering vertical since moving to appliances that don’t restrict the patient to a particular vertical, allowing them to naturally gravitate to their preferred vertical; a theory I have pondered for a while. Having said this, I recently placed a 2mm “V” Tab spacer on a Narval I am using to manage a very obese, very severe apneic and the initial subjective response is a notable improvement, in the patient’s words, “this position is 100 times better”, we’ll see how things play out for him (Confirmation Bias? Not sure). Maybe there is something to the notion of lifting the lid of the box the tongue is in to make more room for it (thanks Todd). The same phenotyping criteria explained in our Vertical discussion was repeated, men need more vertical, women less, obese more, and non-obese less. Using a slightly higher vertical for those with poor nasal patency was also discussed, the theory being that these individuals tend to mouth breath and the increase in vertical may facilitate that process. Of course, we are talking about anecdotal observations here. Todd Morgan shared with us his Evidence Based research on vertical that resulted in the development of the Apnea Guard (discussed in detail below). Todd says, “Theoretically, adding VDO may improve upper airway dynamics by one or two routes: 1) By putting the hyoid sling musculature under additional tension, primarily via the stylohyoid and styloglossus muscles, or 2) By increasing a phenomena known as tracheal tug. My assumptions are based on the dynamic interaction of the infra and supra hyoid muscles and observation on lateral imaging that demonstrates a “smoothing” of the pharyngeal mucosal outline. Whatever the mechanism, we have found in clinical practice that VDO acts as a surrogate to further protrusion in bringing down the supine AHI.” In a current study, Todd is comparing outcomes with patients wearing the low, medium and high Apnea Guard trays, all advanced to 70% protrusion. This should be interesting.

One clinician establishes vertical using the following phenotype characteristics. If the patient has a large maximum opening, large chin and strong bite he uses an 8mm vertical, provided the patient can comfortably manage that vertical. He uses the Airway Matrix system in taking his bite. Of course, this is not Evidence Based. Another device that can be used to facilitate varying vertical is the Andra Gauge.

So, the majority of clinicians start their process with the notion that vertical should be kept to a minimum, which is the default literature position, establishing a vertical incisal edge-to-edge opening of 2-3 mm. A subset then increase vertical from there, based on the vertical required by the chosen appliance, evaluations using tools such as Airway Metrics, Andra Gauge, pharyngometry etc, or insights derived by clinical or anecdotal observations of verticals associated with superior outcomes for particular phenotypes.

As a caution for all this vertical alteration, it was discussed that increasing vertical has the potential of creating increased strain or sprain of the ligament attachments, especially with and during para-function. So, if you are considering altering vertical, it would be wise to “Alter vertical with Care and in Small increments”.

Evaluating the airway using Acoustic Reflection and CBCT was also discussed. Of course, of the two, Acoustic Reflection is the less intrusive. Despite the fact that there is no literature tying improvement in the airway as evaluated by these devices during wakefulness to actual improvements of airway behavior during sleep, there are many clinicians that find this evaluation a useful adjunct in establishing their appliance start position. The use of Pharyngometry to evaluate benefits of varying vertical was also discussed. Regarding CBCT, of course, the major concern was excessive radiation exposure and the lack of Evidenced Based rational for its use to establish the starting position for a sleep apnea appliance.

We had the good fortune of having Shouresh Charkhandeh (over 500 MATRx cases) share his insights with us. Quite frankly, these insights have me very excited about what this remote control technology has to offer our field. Unfortunately, there was not much discussion by varying clinicians about this relatively new approach. Perhaps, due to how little it has penetrated the marketplace, approximately 150 centers across North America. It is extremely unfortunate that the current MATRx business model does not fit with the way Sleep Medicine works. It requires everyone involved doing the “Right Thing” and that is simply asking a bit much. If Sleep Medicine were practiced in that manner, many more appliances would be prescribed than is currently the case. However, recently, I heard about the next generation of this device that will put the MATRx in the Dentist’s hands, allowing a Dentist to do the same evaluation in the patient’s home, much how we currently use Home Sleep Tests (HST) to help calibrate our appliances (ETA approximately 18 months). This has me very excited for the same reason I routinely use a HST to help calibrate my appliance; it will simply up my game. I suspect that we will receive the same level of push back from the Physicians as we currently have regarding our use of HST, even though we are not using HST to screen, diagnose or establish “Official” efficacy. The reasons for this pushback are transparent and not in the patient’s best interest. However, I will continue to use HST as long as it is legal for me to do so under my licensure because quite frankly, it helps me do a better job, the same will apply to the Portable MATRx when it becomes available to me. At a recent conference, I shared the following with John Remmers, “when the mobile version of this device becomes available, make sure my name is first on the list, I’ll buy it site unseen”.

The importance of establishing a good “work flow” with the Sleep lab was discussed and Shouresh pointed out that the upfront time spent with the lab to ensure a good “work flow” pays off once everyone knows what they are doing. It was also pointed out that this protocol advocates moving directly to the “Sweet Spot”, much like the protocol used with CPAP titration. Personally, I question what impact this may have on patient “adherence”. One of the major differences between the way Dentistry and Medicine approaches these patients is our connection with the patient and concern for their comfort and ability to “actually wear” their device. I don’t think we have come to have a much higher “adherence” rate than CPAP by accident; we have earned it, and I question whether it would remain as high if patients were expected to wear their appliance in the final position from the get go. Having said that, Shouresh shares with us that he routinely (85% of the time) goes right to the sweet spot. He does this when the target position is less than 80% of protrusive range, and reports that patients manage this with very little in the way of the side effects that some (including myself) would be concerned about. I find this very interesting. Perhaps the benefit of going to the “Sweet Spot” immediately which results in an “immediate” resolution of the OSA, reduces the typical side effects we experience when we work towards the most effective position in a step wise fashion; I would never of thought that. If the final position is between 80-100%, Shouresh starts them at 70-80% and asks them to titrate to the AP position provided by the test over a few weeks.

Shouresh points out to us that “the MATRx is not a bite technique, it is a test that identifies responders to OAT (prior to making an appliance) and more importantly gives the clinician/dentist an objective data on how the patient’s passive pharynx/ airway responds to mandibular protrusion (during sleep); which could then be used as another additional info to help treatment plan properly. It also provides you with an AP position for the responders, at which the patient’s respiratory events/AHI will be well controlled (50% reduction AND below 10).Once I know the patient is going to respond to OAT, I will focus on the bite registration and starting point. Here are some of the factors that should be taken into consideration when doing the bite registration, to make an appliance comfortable; Vertical, Lateral, AP, Yaw, Pitch, Roll, Muscles, Lip Competency, arch form, any internal derangement, … and many more, to make the appliance anatomically and physiologically correct. This can be achieved through many techniques (most of them have been discussed already in this discussion), depending on the dentists training and occlusal philosophy and most importantly patient’s characteristics. My personal preference is what I call Dynamic techniques; any technique that takes patients muscles and physiology into consideration (Phonetic bite, NM technique / TENS / EMG’s) and is not just based on hard anatomical landmarks (such as Conventional use of George Gauge at 50-70%)”I simply quoted Shouresh here because he so eloquently summarized so much in so few words that it would be criminal to change it up.

Shouresh also explained that he uses the MATRx to establish the level of protrusion (not a specific point, but rather a zone) and then takes a bite with his choice of method, which may or may not involve varying vertical. He also shared that their studies show that the AP position (% protrusion) is independent of patient’s baseline AHI and BMI, ranging from almost no protrusion, to 100% in some cases, with “Median” being about 70%. These statistics suggest that half of the patients we are currently treating do not require the commonly used 70% protrusion, so we are essentially over-protruding half of our patients, potentially causing unnecessary side effects. Using the MATRx protocol helps avoid making an appliance for non-responders helps to ensure the patient is not protruded more than necessary, and negates the need to titrate appliances based on symptom relief, which is the current “standard of care”.

Knowing the optimum position upfront also allows Shouresh to better treatment plan his cases. He finds that certain designs/appliances work better at different levels of protrusion, a process he refers to as “Position Based Design”. He also points out that patients requiring 90-100 % protrusion that also demonstrate an inability to maintain that position, are best steered away from an oral appliance. In essence, the MATRx helps to identify responders and reduces titration efforts (time). This is particularly important when considering that it establishes responders that have severe OSA that may not typically have the opportunity to try an appliance until they have already failed CPAP. Currently, about 5% of patients end up with an oral appliance. With MATRx establishing that 50% of patients tested are responders, if used routinely, this protocol has the potential to increase patients treated from 5 to 50%. He also points out that it does not have to be a “yes” or “No” tool. Even non-responders can be offered an appliance if they are CPAP intolerant to obtain some level of relief or to consider “Combo OA-PAP” therapy. Finally, ~60% of severe patients are positive responders; typically (without MATRx) these patients would not be offered OAT as a first line of therapy.

Shouresh explains his clinics protocols as follows:

MATRx for anyone with AHI of over 10 or high risk/very symptomatic

If “non-responder”, recommend CPAP-trial as first option and then OAT

Patient can try CPAP, if non-compliant, they can still have an oral appliance

The MATRx protocol simply helps place the options in the right order based on objective data. All patients are offered a choice of CPAP or OA regardless of their AHI, if they choose an OA, then a MATRx is prescribed. For patients non-compliant to CPAP the benefit of the MATRx is confirmation that the OA will work, often helpful in having the patient committing to the fee which may not be covered by insurance. The MATRx is not designed to replace anything. It is designed to improve patient care, and be used as a tool by a well-trained clinician. Just like any other technology, it is only as good as the information provided and the user.

Another “Evidence Based” approach for establishing an appliance starting position was discussed by Todd Morgan, the Apnea Guard. An article comparing the recommended Apnea Guard protocol to the conventional jaw advancement approach (which involves systematically advancing the jaw over a period of time), can be found HERE

The Apnea Guard protocol demonstrates clinical utility for the following circumstances; immediate treatment of OSA while the patient is waiting for their custom device, post surgery, and to predict the correct starting position of an oral appliance. Please keep in mind that this study involved just 30 subjects, which begs for the need of further research involving a larger “n”. This study demonstrates that Apnea Guard protocol performed with equivalency to custom appliance therapy when using the algorithm that correctly predicts the optimal starting position using both vertical and protrusive components. It also demonstrated that use of the Apnea Guard provides savings in patient follow-up appointments and overhead expenses by reducing the number of in-office visits prior to establishing an endpoint position. Of course, these savings are based on the conventional slow titration towards the “sweet spot” and become insignificant if the same aggressive approach is taken with a custom appliance as the protocol used with the Apnea Guard.

Todd, like Shouresh above, also discussed the notion of jumping right to the 70% protrusive position from the get go, and that this more aggressive protocol seemed to result in fewer complications and side effect complaints, his theory being that a patent airway is the key to reduced muscle tone and improved comfort. Case studies have reported that oral appliance efficacy diminishes after a period of time at 60% protrusion, necessitating subsequent advancement. This research found that the Apnea Guard at 70% protrusion resulted in a similar result as the conventional progressive advancement method in 80% of cases. Future studies will compare the impact of initiating therapy at 60% vs.70% protrusion and how this relates to reports of morning muscular discomfort.

The timing of when to perform the efficacy outcome study also requires further consideration. First night of therapy sleep studies may be useful in identifying patients who respond to oral appliance therapy, but it is unclear whether these initial results can also establish that the appliance has been optimally calibrated. The Apnea Guard is limited to 30-nights of use based, in part, on the assumption that patients with no contra-indications can safely wear it for a short duration.

One of the concerns about using a trial appliance such as the Apnea Guard is that patients may get a “wrong and negative” impression of the comfort of a custom oral appliance. Patients in this study did find the custom appliance more comfortable, but actually preferred the Apnea Guard to no therapy. The authors stressed that to avoid a negative bias toward OAT developing during the trial period, patients need to be educated that custom appliances are more comfortable and that excessive salivation during sleep will subside.

Studies are underway to demonstrate that the “Efficacious” Vertical and Protrusive setting of an Apnea Guard, captured by extracting the retention material used for the bite registration from the appliance, can be used as a bite registration in the fabrication of a custom appliance, that results in continued efficacy; potentially reducing the customary calibration efforts and also facilitating the efforts of a less experienced clinician to provide effective therapy. Of course, patients can continue using the Apnea Guard by simply refitting it with a second set of retention material for use while they are waiting for their custom appliance to be fabricated.

For those patients that hesitate to proceed without some evidence of efficacy, this device could provide that evidence, and result in the actual construction bite. Something other temporary appliances do not do. Also, for those clinicians that use an appliance that cannot be easily altered from a vertical perspective (like Nylon 3D printed appliances), this device allows one to evaluate the impact of vertical prior to making the custom appliance. Another thing I particularly like about this device is that you are getting information based on the “normal” sleep experience, in the comfort of the patient’s own bed. Much more meaningful than what you get in a sleep lab setting. Pair it up with a HST and I think some extremely valuable information can be obtained. I have some in my office now and I am going to selectively try this protocol out. We’ll see how smoothly it goes.

(Todd Morgan, Barry Glassman, John Viviano)

Phonetic Bite:

The Phonetic Bite group re-confirmed that their start position, is usually at or within 1-2mm of their end position. This starting position is where the phonation takes the mandible to during speech (when counting from 60-75). Adjustment Considerations include patient overbite and how much vertical is needed to accommodate the appliance of choice. It is claimed that this approach results in a comfortable position for most because it’s a position that the patient is accustomed to taking throughout the day when they speak. The claim is that this bite position rarely if ever results in complaints of TMJ discomfort.

When I observe a clinician taking a Phonetic Bite, it looks like somewhat of a “slight of hand” parlor trick that results in a bite that is then altered depending on vertical needed by the appliance design. Although it is really hard for me to understand how this could possibly be related to the airway, and have doubted it for years, I have now seen objective proof of it working! Daniel Klauer and I are involved in an investigation of 20 retrospective consecutive patients treated with a appliance fabricated using a Phonetic Bite compared to 20 retrospective consecutive patients treated with an appliance fabricated using a usual and customary jaw advancement protocol; both resulted in the same outcome, based purely on reduction in AHI, imagine that! Of course, this can only be considered a pilot study and says nothing about the claims of fewer side effects associated with a Phonetic Bite Protocol. So, more work is needed here, both with a larger number of patients, and documentation of short and long-term side effects so proper statistics can be performed. Notwithstanding this, it simply amazes me that the jaw brought to two VERY different locations, results in a similar drop in AHI (no statistical difference).

(Daniel Klauer, Dennis Marangos, John Viviano)

Over the Top Diagnostics:

Jaw Tracking, Joint Vibration Analysis and CBCT’s were also discussed to help establish the best starting position. Notwithstanding the absence of Evidence Based Literature to support the use of these procedures and techniques for this purpose, a number of clinician’s stated that they aide in establishing a better starting position; their view on this is that the literature will catch up. To these clinicians I ask the following question, “If you were being treated for a medical condition by a Physician, would you prefer that the Physician used protocols that were solidly supported by Evidenced Based literature, or would you be OK with the Physician simply doing what he thought best? I know which I would prefer.”

A strong “Caution” was made about the notion of representing the use of a CBCT to be “Standard of Care” in assessing the TMJ for potential future issues, or to establish potential “Efficacy” when making a Sleep Apnea Appliance. These are simply not Evidence Based Claims. To clarify, a “Usual and Customary” screening for TMD is the “Standard of Care” in evaluating the TMJ for potential future issues, and currently, there is no Evidenced Based methodology to image the airway during wakefulness that can be used to determine appliance efficacy during sleep. PERIOD!

(Dennis Marangos, Tim Mickiewicz, John Viviano, Barry Glassman)

Drug Induced Sleep Endoscopy:

The use of Drug Induced Sleep Endoscopy to aide in establishing the best starting position was discussed. The consensus being that although this can be useful for research, it is not practical for regular patient care.

(Gina Pepitone-Mattiello, Steve Lamberg)

Muscle Relaxation and Reduction of Inflammation:

The notion that deprograming the patient’s customary and habitual bite through physiotherapy plays a role in establishing the best initial bite registration was discussed. The “theory” being that the patient’s “comfortable normal bite” may not be a “healthy bite”. If certain muscles such as the pterygoids are not balanced and one side stays contracted or fires slower it causes the jaw to rotate in a yaw plane. Taking a bite registration without correcting for this potentially locks them into a comfortable but unhealthy bite with the sleep appliance. By implementing a regimen of physiotherapy prior to taking the initial bite registration, a “Balanced Muscle Bite” can be established. Physiotherapy is also conducted at appliance insertion, the net result, side effects appear to be minimized and the patient maximum range of motion appears to increase.

When considering this clinician’s approach one should also consider that he uses a Mosses bite, and provides a Mosses appliance. Not much play with this appliance in the mouth and perhaps these concerns may be more about the choice of appliance (Monoblock like). Tony published an article explaining his modified Mosses Bite Technique on the American Sleep and Breathing Academy website for those that wish to read more about it HERE.

Also, for those interested in watching a video of Dr. Moses demonstrating how to take a Mosses bite, this can be viewed online at:

https://www.youtube.com/watch?v=gpPrjf3VSWw.

After viewing this video Steve Lamberg asked, “How does establishing the most comfortable vertical and protrusion translate into the best starting position?” The absence of both “Science” and “Logic” makes this a stretch for many to believe. Yet, patients are effectively managed using this bite registration! The point was made that it depends on how you define the “Best Starting Position”, is it the best for “Patient Comfort”, or for “Efficacy?” An argument was made that if one uses the “Best” starting position that is defined as being “Most Effective”, but the patient can’t tolerate wearing the appliance, that would in fact be the “Worst” starting position, not the “Best” starting position.

The use of Low Level Lasers and the “Aqualizer”, a self-adjusting oral splint were also discussed; both used to help “relax” the TM joints, reduce inflammation and muscle tension prior to taking a bite registration. Information on the Aqualizer can be found at: http://www.aqualizer.com

Of course, this entire discussion on muscle relaxation and reduction of inflammation is completely anecdotal. With the number of variables involved, it is very difficult to evaluate this with proper research. Factors such as type of bite registration, degree of advancement, efficacy of therapy, appliance design, are just some of the variables potentially influencing what one will observe when investigating these issues. The good news, there is no evidence that you can do any harm with these techniques.

Use of the pharyngometer coupled up with the Airway Metrics system was discussed, enabling the evaluation of both vertical opening and mandibular advancement. Use of the SnoreScreener to help isolate a position (both vertical and advancement) that results in the best resolution of snoring was reviewed, and use of the pharyngometer to evaluate the effect of the chosen position on the airway volume. Of course, these concepts are not Evidence Based, but some clinicians find them helpful in establishing their start position.

Evaluation of the nasal passages with a Rhinometer to establish nasal patency was also discussed. The Acoustic Rhinometer is literature validated for this purpose and can be used along with a nasal decongestant to determine if poor patency is caused by bone or soft tissue. However, for our purposes as Dentists, that will not be treating the issue but rather screening for it, simply, placing your finger on one nostril and asking the patient to breath through the other, one nostril at a time, coupled up with a few strategic questions would likely provide you with all the information you need to make a referral.

Performing the Cottle Maneuver can help to establish those individuals that may benefit from a simple nasal valve dilator, as oppose to those that may have a more serious problem requiring surgical intervention by an ENT. You can watch it being performed by clicking the following Link:

Nasal Valve Dilators can be viewed at this website: https://www.maxairnosecones.com.

If the Cottle maneuver does not make a difference, middle turbinate hypertrophy and/or polyps or perhaps septal deviation and/or allergies might be the issue necessitating an ENT referral.

There has been much discussion about using measurements or evaluations of the airway during wakefulness to predict how it will behave during sleep. However, to date, there is no Evidence Based literature to support these notions, regardless of the technique used. Interestingly, even the MATRx approach, which evaluates the airway during sleep, results in both false positives and false negatives.

Regarding musculature, all sorts of devices and techniques were discussed to help the patient deal with wearing an oral appliance with minimal untoward side effects. What was said:

The correct “Cant”, established with the Phonetic Bite, results in fewer TMJ related and muscular side effects

Muscular physiotherapy and treating the musculature with a laser or Aqualizer prior to taking a bite registration results in fewer patient pain and comfort issues

Remarkably, we have clinicians not doing these procedures and not experiencing the rampant side effects some claim will occur without the benefit of these techniques and protocols. Maybe I’m being too simplistic in my thinking, but it seems to me that being respectful of the patient’s comfort and ability to tolerate a particular jaw posture and ensuring the appliance is balanced and fitting properly is all that is required to avoid the rampant, earth shattering side effects that are forecasted to happen unless a certain technique or protocol is used. Once again, research is required to establish Evidenced Based literature regarding the use of these techniques and protocols.

The number of varying bite registration techniques discussed is actually quite remarkable. Some, resulting in the mandible being in a similar position and others in a quite different position; yet all professing to work well. However, the only Evidenced Based approach is that of mandibular advancement. Notwithstanding this, we have clinicians opening vertical, using jaw positions that result from making specific sounds and others based on muscular balance and yet others based on the most comfortable vertical and protrusive position etc. This begs the following question; how can moving the mandible to all these different positions result in a similar and acceptable outcome? There is no evidence that any particular technique works better than another. And although it is difficult to understand how some of these approaches work, it is equally difficult to imagine that educated clinicians would continue to use and stand by a particular protocol that does not work. In the end, their efforts have to pass the “Polysomnography” test! Just sayn 😉 So, in the absence of any evidence to the contrary, I have to accept that they all seem to work. Leading to the following conclusion:

It seems to be more about moving the jaw, rather than where you move the jaw.

Having said this, I think it is important to emphasis that the only Evidenced Based Literature support is for mandibular advancement. Furthermore, the literature suggests that Excessive Vertical Opening can be detrimental to airway patency. Ultimately, all of the starting jaw positions that were discussed strive to establish a jaw posture that the patient can comfortably tolerate and adjustments are made from there, to other jaw postures that the patient can comfortably tolerate. Barry Glassman said it very well, “There is no relationship between the laxity of the collateral ligaments, the eminence angles and the state of the stylomandibular ligaments (those factors that control protrusion) and the effect on the pharyngeal musculature during sleep”. In fact, one does not really know what position is the best starting position and basing it on a percentage of the jaw’s range of motion simply defies logic.

Consider the following:

Matrix identifies responders at all levels of protrusion

Other Bite Techniques result in responders at varied levels of protrusion and vertical opening

A comparison of outcomes using appliances constructed using the Phonetic Bite to appliances constructed using Usual and Customary Jaw Advancement, results in “No Statistically Significant Difference” in the patient’s response to treatment. Even though the patient’s ended up in a very different jaw position.

It seems to me that there is plenty of anecdotal evidence to suggest that Kent Smith is correct. Quoting Kent for a second time, “Hey, it’s all a guess anyway!”

Whichever technique is used, it appears to involve repositioning of the mandible and then further repositioning until both “subjective symptom” and “objective AHI” resolution occurs. The exception to this is the Evidence Based tools and associated protocols that have been developed that allow us to evaluate the impact of varying Jaw position during sleep; the Apnea Guard and the MATRx. Both of these are discussed in some detail and both show much promise in helping us to establish responders and also the optimum jaw position. We are in dire need of more good research on the possible benefits of varying Vertical and use a particular Jaw Postures, such as that derived by the Phonetic bite that results in much less protrusion. The similarity in outcomes in the retrospective study on Phonetic vs. Advancement Bites suggests that an increase in Vertical may in fact be a surrogate for jaw advancement. Todd Morgan has developed a protocol to use along with the Apnea Guard that helps to account for variance of vertical based on patient phenotype, something he has developed from observations in his previous research. Of course, if this phenotyping is further confirmed in the literature, I am sure that this same feature could be added to the MATRx system. Very exciting times for Sleep Disorders Dentistry.

Considering all of the potential distractions a clinician new to this field is exposed to, I think Barry Glassman provides some very solid advice, “Long ago I learned that making as good a diagnosis as possible (with some degree of reality) – and taking the approach of doing the least we have to do to help our patients, taking the time to listen to their concerns and goals… “ is all that is needed, no more and no less.

This turned out to be a very lengthy and at times quite heated discussion, I would never of expected this for a discussion on establishing a starting point for a sleep apnea appliance! The passion that these clinicians practice with is to be commended. I am truly appreciative of all that participated and sincerely hope that this summary consensus will be helpful to clinicians new to this field and perhaps thought provoking to those of us that have been at it a while. I look forward to further discussions on the SleepDisordersDentistry LinkedIn Group.